Here is one by Marr & Tang
Their comment on the <5 >5 IPC paradigm is it defies physics.
Its from 2021 pubmed.ncbi.nlm.nih.gov/34415335/
A simple one illustrating a critical error (also 2021)
Recognising its airborne has always been No 1 - unfortunately not for @WHO nor IPC
What cleaning air does / does not do - excellent mental model.
The one illustrates close space transmission. The use of the term 'close contact' is a misnomer - its a SPACE wherein transmission happens yet the actual mode of transmission is unknown - and crucially may not involve contact - close contact does not evidence droplets (@WHO)
And another one... explaining transmission
Here is one I did to illustrate what factors people were using to assess mask use (blue circle) and all the factors outside the circle that should have been considered.
Also my latest suggestion to omit using 1 word descriptors (airborne or droplet ) but to use a source - to - infection pathway model for evidenced transmission routes
[NB When you use this model contact is not the No 1 way to get an HAI]
So its the absence of mental models that is the problem. Its the @WHO and all IPC organisations who have failed to state its airborne when the evidence for droplets does not exist.
Its @WHO videos and tweets (still up) telling people its not airborne - sans evidence.
And another mental model illustrating how IPC has not stepped up to its responsibilities...
The @WHO and CDC, Dept of Health and noted guidance all have different places where droplets land - ridiculous.
This brilliant work is also from 2015,
IPC have no excuses - those who reviewed evidenced and determined 'its droplets' got it wrong.
Mental models will not solve this until IPC esp @WHO and UK stand up and say we were wrong.
@JOHNJOHNSTONED pubmed.ncbi.nlm.nih.gov/25816216/
Also, the @WHO must stop producing guidance until it ceases to mis-reference. An example from a 2022 doc.
2 references in support of HH being 'most effective' don't mention hand hygiene.
IPC must correct their physics defying statements
Mental models - yes - if evidenced
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They have withdrawn masks in Scotland's Healthcare system and referred 'concerned staff' to complete a risk assessment. healthyworkinglives.scot/resources/form…
Lets fill out their risk assessment...
I am (for the form) a ward manager
Describe the task:
Any patient-to-HCW, HCW-to-HCW, patient-to-patient, or visitor-to-patient or HCW interaction in any close space, e.g. conversation or stethoscope range
or when ventilation poor just being on the ward.
Where is the task to be carried out?
Every minute of every day on this ward we are continuously interacting and at risk of inhaling someone else's exhaled air + virus.
Inhalation at distance is also a risk because we have no idea of the indoor air quality - no indicators.
Considering how the 'collective we' made Mode of Transmission Errors - some possibilities
a) we turned doubt in to certainty, the use of qualifiers in original work were turned into fact, eg.
'droplets have traditionally been defined as ...'
became
'droplets are defined as '
a) More doubt to certainty
Dr X et al showed that viruses can get in to the eyes, nose and mouth
was translated to
Dr X et al showed that all droplets get in via the eyes nose and mouth
b) We interpreted transmission in a 'close space' as evidence of droplets; actually it was evidence of close space respiratory transmission - not evidence for droplets
7 slides showing that neither CDC nor WHO presented evidence for the existence of droplet transmission
You may have seen this from the WHO most pandemic refs refer to it - note lack of evidence (its not in 5), and in the def or aerosols it says 'its not yet clear'
This is from the CDC which cites references showing 'outbreak evidence', 'experimental evidence' and 'aerosol dynamics'....
Only relevant outbreak reference is 101 - lets get it...
Here it is. Med students walk in to 8-bedded bays interview pts and leave. Index case (SARS) bed 11.
3 in droplet range get SARS; 4 outwith droplet range also get it. Authors conclude close = droplets but aerosols were not excluded.
CDC cites this as evidence for droplets...
In this preprint I believe there is a call for RPE - which is excellent medrxiv.org/content/10.110…
The authors states...
"Appropriate PPE and mask use are essential as SARS-CoV-2 is frequently detectable in the air surrounding positive patients."
Specifically stating:
"We believe our data supports the use of FFP2/3 medical masks for HCWs caring for COVID-19 patients, particularly for those with prolonged contact in line with HSE guidelines 15"
However I believe they may have made an error....
Reference 15 is to not to the HSE but the now withdrawn "UKHSA guidelines Infection prevention and control for seasonal respiratory infections in health and care settings (including SARS-CoV-2) for winter 2021 to 2022. Updated 17 January 2022. "
The IPC world entered the pandemic with an erroneous paradigm for the transmission of respiratory infections.
What if this was not the only erroneous paradigm? What if we have to go back and review all routes of transmission?
Here is the latest MRSA guideline 2021 - the focus is on prevention of transmission - good.
'MRSA is easily spread by multiple routes' - unhelpful which ones?
I can only find one transmission route mentioned - 'hands' and the ref is 195.
Ref 195 is a review focussed on summarising the existing evidence for hands - no other routes considered.
But what about the other routes that are not considered?
Monkeypox - NON EXPERT HERE
Just going to highlight some variations in transmission definitions.
NB when we get the definitions wrong we get the precautions wrong (See COVID for details).
Note - none of these definitions come with references.
The @WHO as already stated describes inhalation of the virus as FOMITE Transmission.
But if you can inhale the virus from bed linen why can't you inhale from exhaled breath when its in resp secretions?
Specifies skin-to-skin - does this mean the virus invades intact skin ?
Ok its the @CDC next
Absolutely no inhalation going on whatsoever here.
Unsure about the respiratory secretions when cuddling?
Skin to scab or lesion again - no specifics about the ability to invade intact skin or does it need to touch another site?